Conventionally, a vapor compression refrigeration cycle device having an ejector as depressurizing means (hereinafter referred to as “ejector refrigeration cycle”) has been known. For example, Patent Document 1 discloses an ejector refrigeration cycle of this type in which multiple evaporators for cooling different spaces to be cooled are provided, and the respective evaporators are connected in parallel to each other.
In more detail, the ejector refrigeration cycle disclosed in Patent Document 1 has a cycle configuration that includes gas-liquid separation means for separating a refrigerant flowing out of a diffuser portion (pressurizing part) into gas and liquid, distributes a liquid-phase refrigerant separated by the gas-liquid separation means to multiple evaporators, merges the respective refrigerants flowing out of the multiple evaporators, and guides the merged refrigerant to a refrigerant suction port of the ejector.
However, in the cycle configuration of the above type, for example, if a passage pressure loss of a refrigerant path extending from the gas-liquid separation means to the refrigerant suction port through a first evaporator is different from a passage pressure loss of a refrigerant path extending from the gas-liquid separation means to the refrigerant suction port through a second evaporator, the refrigerant hardly flows into the refrigerant passage larger in the passage pressure loss. As a result, a sufficient amount of refrigerant cannot occasionally appropriately be supplied to an evaporator arranged in a refrigerant passage large in the passage pressure loss.
Under the circumstances, in the ejector refrigeration cycle of Patent Document 1, a refrigerant suction capability of the ejector is improved with the configuration of a so-called supercritical refrigeration cycle in which a pressure of a high pressure side refrigerant of the cycle which flows into a nozzle portion of the ejector becomes equal to or higher than a critical pressure of the refrigerant. The refrigerant is drawn from a downstream side of the multiple evaporators with the high suction capability, to thereby appropriately supply the refrigerant to the respective evaporators.